Minimus is a GUI frontend for Yahoo’s YUI Compressor. Instead of using inconvenient and slow websites to compress your JavaScript and CSS, you can do it right on your Mac.

Add files to the queue by dropping them on the Dock icon (or by using the File menu) and press the Minify button to start the process. In no time at all, copies with a .min.js or .min.css extension will appear alongside the originals.

Minimus is a free download, but donations are appreciated if you find the app useful. Requires Mac OS X 10.6 Snow Leopard.